JPH05308075A - Plating device of semiconductor wafer - Google Patents

Abstract

PURPOSE:To prevent a plating liquid which is blown up from sticking to a cathode by covering the entire cathode with a cathode protection part and a semiconductor wafer which is placed on a wafer support surface when performing plating treatment. CONSTITUTION:A cathode protection part 15 protrudes from the inner-periphery wall of a recessed part 12 nearly at right angle and is formed and the upper surface is a wafer support surface 16. The tip side of a cathode 19 is laid out while it protrudes from the wafer support surface 16 of the cathode protection part 15 in a state where the cathode 19 is energized upward by an elastic force of a spring member 20. Also, a seal member 22 is provided on the wafer support surface 16 of the cathode protection part 15. While the semiconductor wafer 24 is set, the entire cathode 19 is completely covered with the semiconductor wafer 24 and the cathode protection part 15 and at the same time airtightness of the cathode 19 is further enhanced by the seal member 22. Plating liquid is blown up from a plating liquid supply hole 13 in this cover-up state, thus preventing the plating liquid from sticking to the cathode.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor wafer plating apparatus used for forming bump electrodes on the surface of a semiconductor wafer.

[0002]

2. Description of the Related Art Conventionally, as an apparatus of this kind, Japanese Patent Laid-Open No.
There is one disclosed in Japanese Unexamined Patent Publication No. 6-5318. FIG. 3 is a vertical sectional view showing the conventional semiconductor wafer plating apparatus, and FIG. 4 is a plan view of a conventional plating cup.

In the illustrated plating apparatus 50, reference numeral 51 is a plating cup, and a recess 52 is formed in the plating cup 51 with the upper part thereof opened. Further, the plating solution supply hole 5 is provided below the recess 52 of the plating cup 51.
3 are formed in communication with each other, and a mesh-shaped anode 54 is provided at the upper end of the plating solution supply hole 53.

On the other hand, a plurality of (six in the illustrated example) protrusions 55 are formed on the upper surface of the plating cup 51, and each protrusion 55 has a step 57 for supporting the semiconductor wafer 56. Are formed. Further, a needle-shaped cathode 58 is provided on the inner peripheral surface of the protruding portion 55.
The pointed portion on the front end side of is projected and arranged above the step portion 57.

Further, reference numeral 59 in the drawing denotes a lid disposed above the plating cup 51, and a contact pin 60 made of an elastic material corresponds to the above-mentioned cathode 58 on the lower surface circumferential portion of the lid 59. Are provided. A pressing member 61 formed of, for example, a leaf spring is attached to the lower surface side of the lid 59.

Now, a procedure for plating the surface of the semiconductor wafer using the conventional plating apparatus 50 will be described. First, the semiconductor wafer 5 is placed on the step portion 57 of each protrusion 55 with the front surface side of the semiconductor wafer 56 facing downward.
Place 6. Next, the semiconductor wafer 56 is pressed from above by the lid 59 and the pressing member 61. This pressing force causes the tip portion of the cathode 58 to bite into the surface of the semiconductor wafer 56.

Then, it is confirmed whether or not the semiconductor wafer 56, the cathode 58 and the contact pin 60 are electrically connected to each other. After the confirmation, the power of the plating apparatus 50 is turned on to operate the apparatus. As a result, the plating solution stored in the tank (not shown) is led out to the plating solution supply hole 53 through the pipe 62 in the figure, and further blown up from the plating solution supply hole 53 through the anode 54. The sprayed plating solution is sprayed onto the surface of the semiconductor wafer 56 placed on the step 57, and flows out from the gap formed between the upper surface of the plating cup 51 and the surface of the semiconductor wafer 56. It is housed in a container (not shown) and returned to the above-mentioned tank through a pipe (not shown) again. The surface of the semiconductor wafer 56 is plated by the above procedure.

[0008]

However, in the conventional plating apparatus 50, since the cathode 58 is provided in an exposed state, the plating solution blown up from the plating solution supply hole 53 adheres to the cathode 58 as well. It will be.
Then, a plating layer is gradually deposited on the surface of the cathode 58, which hinders the plating growth on the semiconductor wafer 56 side and causes a variation in the plating thickness on the wafer surface.

Further, conventionally, as a measure against the above problem, the cathode 58 must be frequently cleaned and maintained, and the cathode 58 must be replaced regularly, which requires a great deal of labor and man-hours. Was there.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a semiconductor wafer plating apparatus which prevents the plating solution from adhering to the cathode.

[0011]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above-mentioned object, and comprises a plating cup having a recess formed in an upper opening and an inner peripheral wall of the recess of the plating cup. A plurality of cathode protection portions which are formed to project at right angles and whose upper surface is a wafer support surface, and a tip of which is formed to have a tapered tip, the tip side of which is located above the wafer support surface of the cathode protection portion. Is placed so that
A semiconductor wafer plating apparatus including a cathode whose rear end side is arranged inside the cathode protection portion, and a pressing member for pressing the semiconductor wafer mounted on the wafer supporting surface of the cathode protection portion from above. Is. Further, a sealing member having a cathode inside is provided on the wafer mounting surface of the cathode protection unit. Furthermore, the above-mentioned cathode is in a state of being biased upward by a spring member provided inside the cathode protection portion,
The tip side is arranged so as to project from the wafer supporting surface of the cathode protection part.

[0012]

In the semiconductor wafer plating apparatus of the present invention, the semiconductor wafer placed on the wafer supporting surface of the cathode protection portion is pressed from above by the pressing member, so that the tip of the cathode bites into the wafer surface. The entire cathode is completely covered by the semiconductor wafer and the cathode protection portion.
Therefore, even if the plating solution is blown up from this state, the plating solution does not adhere to the cathode. Further, the airtightness of the cathode covered with the cathode protection portion and the semiconductor wafer is further enhanced by the sealing member provided on the wafer supporting surface. Further, when the semiconductor wafer is pressed from above by the pressing member, the biting force of the cathode with respect to the wafer surface is appropriately adjusted by the elastic force of the spring member.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of a semiconductor wafer plating apparatus according to the present invention will be described below with reference to the drawings. FIG. 1 is a longitudinal sectional view of an essential part showing an embodiment of the present invention, and FIG. 2 is a plan view of a plating cup in the embodiment.

In the illustrated plating apparatus 10, reference numeral 11 denotes a plating cup, and the plating cup 11 is provided with a recess 12 in a state of being opened upward. A plating liquid supply hole 13 is formed under the plating cup 11 so as to communicate therewith, and a mesh-shaped anode 14 is provided at the upper end of the plating liquid supply hole 13.

On the other hand, reference numeral 15 in the drawing denotes a cathode protection portion, and this cathode protection portion 15 is formed so as to project from the inner peripheral wall of the recess 12 of the plating cup 11 at a substantially right angle, and its upper surface serves as a wafer supporting surface 16. .. A guide portion 17 is integrally formed on the upper surface of the plating cup 11 at substantially the same position as the cathode protection portion 15. The semiconductor wafer is guided by the guide portion 17 and the semiconductor wafer is supported on the wafer support surface 16 of the cathode protection portion 15.
Placed on. In this embodiment, the three cathode protection portions 15 are formed on the inner peripheral wall of the recess 12 of the plating cup 11, but the present invention is not limited to this.

Further, a space 1 is provided inside the cathode protection portion 15.
8 is formed, and the cathode 19 is inserted into a through hole (not shown) formed above the space 18. The cathode 19 is formed such that the tip thereof is tapered and sharpened, the tip side thereof is arranged so as to project upward from the wafer supporting surface 16 of the above-mentioned cathode protection portion 15, and the other rear end side thereof is inside the cathode protection portion 15. It is located on the side.

A spring member 20 made of, for example, a compression spring is arranged in the space 18 of the cathode protection portion 15. The lower end side of the spring member 20 is in pressure contact with the conductive rod 21 led out from the outside of the plating cup 17 into the space 18 of the cathode protection portion 15, and the upper end side thereof is in pressure contact with the rear end portion of the cathode 19. ing. As a result, the cathode 19 is arranged such that its tip end side projects from the wafer support surface 16 of the cathode protection portion 15 while being biased upward by the elastic force of the spring member 20.

In addition, the wafer support surface 1 of the cathode protection portion 15
A seal member 22 is provided on the surface 6. As the seal member 22, for example, an O-ring made of synthetic resin or synthetic rubber is used. And the sealing member 22
Are provided with the cathode 19 disposed inside on the wafer support surface 16. Furthermore, plating cup 11
A lid (not shown) is arranged above the lid, and the holding member 2 formed of, for example, a leaf spring is provided on the lower surface side of the lid.
3 is attached.

Next, the procedure for plating the surface of the semiconductor wafer using the plating apparatus 10 of this embodiment will be described. First, the front surface side of the semiconductor wafer 24 (the side on which the photoresist film 24a and the conductive coating 24b are formed) faces downward, and the wafer support surface 1 of each cathode protection portion 15 is faced down.
The semiconductor wafer 24 is placed on the substrate 6. Next, the semiconductor wafer 24 is pressed from above by a lid and a pressing member 23 (not shown). Due to this pressing force, the tip portion of the cathode 19 is in a state of biting into the surface of the semiconductor wafer 24. At this time,
The biting force of the cathode 19 with respect to the wafer surface is appropriately adjusted by the elastic force of the spring member 20, whereby the cathode 1
The tip portion of 9 is connected to the conductive film 24 b of the semiconductor wafer 24. Further, when the semiconductor wafer 24 is set in this way, the entire cathode 19 is completely covered by the semiconductor wafer 24 and the cathode protection portion 15, and the airtightness of the cathode 19 is further enhanced by the seal member 22.

Then, it is confirmed whether or not the semiconductor wafer 24 and the cathode 19 are electrically connected, and after this confirmation, the power of the plating apparatus 10 is turned on to operate the apparatus. As a result, the plating solution stored in the tank (not shown) is led out to the plating solution supply hole 13 through a predetermined pipe, and further blown up from the plating solution supply hole 13 through the anode 14. The sprayed plating solution is sprayed on the surface of the semiconductor wafer 24 placed on the wafer support surface 16 of the cathode protection portion 15, and is also applied between the inner peripheral surface of the plating cup 11 and the outer peripheral surface of the semiconductor wafer 24. It flows out from the gap formed in the above, is housed in a container (not shown), and is returned to the above-mentioned tank through a predetermined pipe again. The surface of the semiconductor wafer 24 is plated by the above procedure.

As described above, in the plating process using the plating apparatus 10 of this embodiment, the cathode 19 is the semiconductor wafer 2
Since the plating solution is blown up from the plating solution supply hole 13 in a state where it is completely covered by 4 and the cathode protection part 15, the plating solution blown up unlike the conventional case does not adhere to the cathode.

[0022]

As described above, according to the present invention,
During the plating process, since the entire cathode is completely covered by the cathode protection portion and the semiconductor wafer mounted on the wafer supporting surface, the plating liquid blown up may adhere to the cathode as in the conventional case. Absent. As a result, needless to say, cleaning and replacement of the cathode are not necessary, and plating growth on the semiconductor wafer is not hindered, and variations in plating thickness on the wafer surface can be reduced. Further, the airtightness of the cathode can be further enhanced by the sealing member provided on the wafer supporting surface of the cathode protecting portion.
Moreover, even if a slight gap is generated between the wafer surface and the wafer supporting surface due to the warp of the semiconductor wafer or the like, the seal member can reliably prevent the plating solution from flowing around to the cathode. Further, when the semiconductor wafer is pressed from above by the pressing member, the biting force of the cathode with respect to the wafer surface is appropriately adjusted by the elastic force of the spring member, so that even if there is some variation in the film thickness of the photoresist film on the wafer surface. The tip of the cathode can be reliably connected to the conductive coating of the semiconductor wafer.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view of an essential part showing an embodiment of the present invention.

FIG. 2 is a plan view of a plating cup according to an embodiment.

FIG. 3 is a vertical sectional view showing a conventional example.

FIG. 4 is a plan view of a plating cup in a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Plating device 11 Plating cup 12 Recessed portion 15 Cathode protection portion 16 Wafer support surface 19 Cathode 20 Spring member 22 Sealing member 23 Holding member 24 Semiconductor wafer

Claims (3)

[Claims] 1. A plating cup having a recess formed in an upper opening, and a plurality of cathode protections formed to project substantially at right angles from an inner peripheral wall of the recess of the plating cup and whose upper surface serves as a wafer supporting surface. And a tip formed in a tapered shape, the tip side of which is arranged so as to project upward from the wafer supporting surface of the cathode protection section, and the other rear end side of which is the inside of the cathode protection section. An apparatus for plating a semiconductor wafer, comprising: a cathode arranged and a pressing member for pressing the semiconductor wafer mounted on the wafer supporting surface of the cathode protection unit from above. 2. The apparatus for plating a semiconductor wafer according to claim 1, further comprising a seal member having the cathode disposed inside thereof, which is provided on a wafer mounting surface of the cathode protection unit. 3. The cathode is arranged such that its tip end side is projected from the wafer supporting surface of the cathode protection part in a state of being biased upward by a spring member provided inside the cathode protection part. The plating apparatus for a semiconductor wafer according to claim 1, wherein the plating apparatus is a semiconductor wafer.